1. Field of the Invention
The present invention relates to a method for surface treatment of film. More particularly, it relates to an economical method of film surface treatment for the improvement of printability and adhesion properties.
2. Description of the prior Art
There are many instances where plastics film undergoes surface treatment for the improvement of printability and adhesion properties.
The conventional methods of surface treatment for this purpose include sand blasting, wet cleaning, corona discharge treatment, plasma treatment, and so forth. Each of them has a disadvantage of its own. Sand blasting deteriorates the physical properties of the material treated and consequently its use is limited. In addition, it is expensive to carry out. Wet cleaning needs a waste water disposal unit, which makes the treatment expensive. Corona discharge treatment involves difficulty in performing stable operation on account of the variation of surface properties of the web to be treated. Plasma treatment also involves difficulties arising from the operation to be performed in a vacuum. In addition, it is expensive to carry out.